The company, which in effect controls the market in several of the world's raw materials, has teamed up with a former South African politician to table a bid that values South African coal mine Optimum Coal at $1.2bn (£735m).

Glencore bought a 14.1% stake in Johannesburg-listed Optimum and said it had agreements that may increase this to 43.5%.

The Glencore-led consortium said it planned to offer 34 rand (£3) a share to take control of the rest of the miner. However, Optimum has received a rival offer and said it did not view Glencore's offer as a "firm intention" to make a bid.

The commodities trader is understood to be planning to take a 70% stake in Optimum, which is South Africa's sixth-largest coal producer. The remaining 30% would be split between Cyril Ramaphosa, a leading figure in the fight against apartheid and former leader of the mineworkers union who is now a businessman, and a black empowerment organisation.

Ivan Glasenberg, Glencore's multi-billionaire chief executive, said last week that he was "aggressively" looking for bargain acquisitions as the value of the world's resource companies dropped in the market turmoil.

Last week Glencore launched a A$268m (£170m) cash bid to acquire the 27% of Australia-based nickel miner Minara Resources it does not own.

Glencore's director of coal operations, Tor Peterson, said Optimum's mines and ports were an "attractive addition" to the company's existing South African operations. "We expect strong Chinese and Indian imports and concerns surrounding nuclear generation capacity to result in sustained underlying demand for coal," Peterson said.

Shares in Glencore have fallen nearly 22% since their blockbuster $10bn initial public offering in May, wiping hundreds of millions of pounds off the paper worth of dozens of its leading executives. Glasenberg's stake is now worth £1.3bn less than in May. The shares closed down 2% to 412p.